The rise of Vice President Kamala Harris to the top of the Democratic presidential nomination has catapulted new issues and messages – as well as a new vice presidential candidate – into the election campaign, which is now culminating in the final sprint for the White House.

Harris introduced her new running mate, Minnesota Governor Tim Walz, to a large and enthusiastic audience in swing states last week.

Although Walz is a Midwestern governor, it is not a given that he can help Harris win in key states like Michigan, Wisconsin and Pennsylvania. Harris declined to include Pennsylvania Governor Josh Shapiro, who could have given the Keystone State 19 electoral votes, in the race. Instead, she chose Walz, whose state offers 10 electoral votes and who has not endorsed a Republican presidential candidate since 1972.

Harris hopes that Walz’s folksy but tough personality will appeal to a cross-section of Americans.

With Walz, Harris also strengthened her progressive platform, which is intended to appeal to the working class. She will have to show that her policies, which many Republicans dismiss as too radical, will help families across America.

When President Joe Biden dropped out of the race in July, 78-year-old former President Donald Trump could no longer use the Democrat’s age and vitality as a target for his campaign. The Republican was now faced with finding a way to eliminate Harris and Walz.

As the campaign heats up, Trump will try to link Harris to problematic issues like inflation, border security and other Biden vulnerabilities. And he will continue to label her as too liberal to lead the nation.

However, Trump is now the old man in the race, and Harris is bombarding voters in the swing states with a central message: It is time to put the Trump era behind us.

Therein lies the fascinating tactical combat.

With their early, pop-culture enthusiasm, Harris and Walz are trying to build a coalition similar to the one that brought Barack Obama to the White House in 2008 and 2012. Those campaigns were about inspirational messages about the country’s upward trajectory, rather than cliched ideological considerations. Obama’s feel-good message attracted not only Democrats, but also many independents and some Republicans who switched parties.

Harris is not Obama, and she is running against Trump, not the late Senator John McCain, Republican of Arizona and the Republican presidential nominee in 2008.

Facing a barrage of criticism from Trump about her intelligence and whether she consistently identifies as black or South Asian, Harris is trying to craft a positive message that makes Trump a thing of the past.

She would be the first woman to be elected president, which has added to the initial enthusiasm for her campaign.

The problem for Harris and Walz is that if Trump stays true to his message, it will be easy for him to link them to progressive policies that could mobilize conservatives and dampen enthusiasm in the Democratic Party.

Harris, a former prosecutor, attorney general and senator, is from liberal San Francisco. Walz, a former high school teacher, football coach and member of the Army National Guard, comes from one of the most liberal states in America.

Trump called them the “most radical left-wing duo in American history.”

Many Republican attacks were directed against Walz.

As governor of Minnesota, he supported gender-equal childcare, enshrined abortion rights in state law, and provided free college tuition for families earning less than $80,000 a year, including illegal immigrants. He also supports issuing driver’s licenses to illegal immigrants and providing government-run health care for low-income residents.

These positions are more progressive than the positions Walz took as a congressman representing a rural swing district in the state of Minnesota.

Nevertheless, Harris is convinced that Walz is also attractive to other candidates and can offer good opposition to Republican vice presidential candidate JD Vance.

Vance, once a Trump critic, is a 39-year-old Marine Corps veteran who could be seen as the future of the Republican Party.

However, the U.S. Senator from Ohio has come under criticism for previous comments about women, such as when he dismissed some Democrats as “childless cat ladies.”

Democrats hope that issues surrounding abortion rights will generate broad support among women. Vance’s stance of opposing abortion even in cases of rape and incest is in stark contrast to Walz’s.

Because of the clear substantive differences between the two candidates, the presidential race will be a battle for turnout in most parts of the country, including in Texas, where Trump is the favorite to beat Harris. But Democrats are happy that the race remains more exciting than it was when Biden was on the ballot. The margin in the Trump-Harris race could determine the fate of lower-ballot races, including the Senate race between Democratic U.S. Rep. Colin Allred (D-Dallas) and incumbent Republican U.S. Sen. Ted Cruz.

Although the vice presidential candidates are in the news today, experience shows that they will soon fade into the background.

The election campaign is mainly about Harris and Trump, who will debate on ABC on September 10. This could be decisive for both candidates. Further debates and a duel between Vance and Walz are being discussed.

Then things get serious. Trump has already run two presidential campaigns, but he often deviates from the script and can cause controversy at any time.

Harris dropped out of the 2020 presidential primary race before the Iowa Democratic caucuses and must now prove that she has the fortitude needed to see it through to the end.

Regardless of the surprises of the election season, the outcome of the presidential campaign will likely depend on whether Harris can continue her winning streak and distance herself from Biden’s negative aspects, or whether Trump has the discipline to stick to his message and use his rivals’ progressive backgrounds against them.