Vice President Kamala Harris is experiencing a surge in support since launching her presidential campaign just three weeks ago, according to recent horserace polling. This momentum has allowed Harris to reverse a persistent gap that former President Joe Biden could not overcome during his own campaign.

The political landscape has been dynamic in recent weeks, with significant events such as the assassination attempt on former President Donald Trump, the Republican convention, Trump's running mate selection, Biden's withdrawal from the presidential race, and Harris' selection of a vice presidential candidate. However, disentangling the effects of these individual events to establish a baseline for the race is challenging, especially with next week's Democratic convention on the horizon.

As the race undergoes structural changes, certain metrics will be crucial to monitor to understand the true state of the race beyond the horserace polling. Key indicators include Harris' rising personal favorability and Trump's narrowing advantage on the economy, one of his core issues.

Neil Newhouse, the lead pollster for Mitt Romney's 2012 presidential campaign, emphasized the significance of being a fresh candidate in the race: "Presidential campaigns are a marathon, and this one has turned into a sprint. And that tends to favor the candidate who is new on the horizon."

Here are five critical numbers to watch beyond the horserace:

1. Vice President Kamala Harris' Favorability: On June 27, Harris had a favorability rating of 39 percent. Currently, her favorability stands at 45 percent (source: RealClearPolitics average). Throughout the past three years, there has been a significant discrepancy between voters who held favorable opinions of Harris and those who viewed her unfavorably. However, recent polls show that voters are now viewing Harris more positively, with an equal number of likely voters across Michigan, Pennsylvania, and Wisconsin expressing favorable views (50 percent) compared to unfavorable views (48 percent) in New York Times/Siena College polls. However, this positive image may not be permanent, as Trump's campaign has started an advertising barrage aimed at portraying Harris as "dangerously liberal." This could potentially impact her favorability ratings as scrutiny of her record increases following her initial campaign rollout.

2. Support for Independent or Third-Party Candidates: On July 21, 12.2 percent of voters indicated they planned to vote for one of the independent or third-party candidates (Robert F. Kennedy Jr., Cornel West, or Jill Stein). Now, this percentage has decreased to 7.1 percent (source: RealClearPolitics average). This shift suggests that voters are increasingly finding appeal in the main options presented by Harris and Trump. The decline in third-party supporters can be attributed to the surge in popularity for Harris and Trump's favorability uptick following the assassination attempt and convention.

3. Enthusiasm Among Voters: Democrats who are "very enthusiastic" about voting stand at 62 percent, while Republicans share this level of enthusiasm at 63 percent (source: New York Times/Siena College poll of likely voters in Michigan, Pennsylvania, and Wisconsin). This parity indicates that Harris has successfully energized Democrats with her candidacy, bridging the enthusiasm gap between Democrats and Republicans that existed during Biden's tenure as the Democratic nominee.

4. Trump's Lead on Economic Issues: Trump previously held a commanding lead over Biden on economic issues. However, since Harris replaced Biden at the top of the Democratic ticket, Trump's advantage on this front has narrowed significantly. In national NPR/PBS News/Marist College polls, Trump leads by only 3 points on economic issues against Harris. Similarly, across the three Rust Belt battleground states (Michigan, Pennsylvania, and Wisconsin) in New York Times/Siena College polls, Trump maintains a 6-point advantage on economic matters. Harris aims to build her own record on economic issues, with plans to lower costs and address inflation concerns.

5. Perception of Change: Prior to last month, Trump represented change for voters, with two in three expressing concerns about the country heading in the wrong direction. However, with Harris' entry into the race, she now claims the mantle of change and freshness. At 78 years old, Trump faces challenges in maintaining his image as a change agent, especially as he becomes the first person in 80 years to be his party's presidential nominee for the third consecutive election. Trump and his allies will attempt to portray Harris as responsible for the current state of the country due to her role as vice president.

As a flurry of surveys emerges over the coming days, these key metrics will provide insights into the real state of the race. The upcoming two months will be marked by intense polling, offering valuable data to understand the evolving dynamics of the presidential contest between Kamala Harris and Donald Trump.