National betting odds for the 2020 presidential election have tightened between President Trump and former Vice President Joe Biden as the Republican National Convention gets underway.

Real Clear Politics' national betting averages between April and June show Trump as the more likely candidate to win, but Biden took over with a lead as a 24 percentage-point favorite in July.

Since early August, however, the odds have closed, with Biden having a 54.9 percent of winning and Trump having a 44.4 percent shot as of Tuesday.

TOP GOAL AT DEMOCRATIC CONVENTION: PARTY UNITY

President Trump speaks on stage as he visits the Republican National Committee convention site, Monday, Aug. 24, 2020, in Charlotte. (AP Photo/Evan Vucci)

The former vice president tapped running mate and former Democratic presidential nominee Sen. Kamala Harris on Aug 11. Biden's campaign has seen a surge in funding and social media interactions since his campaign made the announcement.

WHAT THE LATEST FOX NEWS POLL SHOWS IN THE BIDEN-TRUMP BATTLE

These betting averages differ from RCP's national polling average, which shows Biden at 50 percent support and Trump at 42.2 percent.

RCP's polling average shows Biden leading in swing states including Wisconsin, Florida, Michigan, Pennsylvania, and Minnesota. Trump tops Biden in North Carolina, according to RCP.

Betting odds were not, however, a reliable guide during the 2016 presidential election. Data from PredictWise showed Democratic candidate Hillary Clinton with an 88% chance of winning, while Trump had a 13% chance of victory.

CLICK HERE FOR THE FOX NEWS APP