The race to challenge Trump: Biden strengthens lead in polls, endorsements

Important first races

Biden also leads in all three first key state races, according to polling analyses by RealClearPolitics that was accessed Tuesday morning, with two of the three seeing an increase in Biden support.

In Iowa, the first state caucus, Biden leads in the RCP average with 23.7 percent, which is comparable to polls taken earlier, though about 3 percent smaller than before he declared his candidacy.

Behind him in Iowa are Sanders with 19.7 percent, Mayor Buttigieg with 11.3 percent, Sen. Harris with 7.7 percent, and Sen. Warren with 7.3 percent.

In New Hampshire, which is the first official primary, Biden has greatly increased his lead compared to before he announced his campaign, going from 24.5 percent last month to 28 percent in data accessed Tuesday.

Meanwhile, Sanders, who had 22.3 percent support in New Hampshire last month, has seen his support decline to 15 percent, though he is still second among the candidates.

Behind Sanders in New Hampshire are Buttigieg with 10.5 percent, Warren with 8 percent, Harris with 6 percent, and, in a tie, O’Rourke and Senator Cory Booker of New Jersey with 2.5 percent.

Biden’s lead in South Carolina has increased from 37 percent earlier this year to 41.5 percent as of Tuesday morning, putting him well ahead of second place candidate Sanders at 18 percent.

Behind Sanders in South Carolina are Harris with 9.5 percent, Warren with 6.5 percent, Sen. Booker with 5 percent, and Buttigieg with 4 percent.