New poll shows four top-tier 2020 candidates in Iowa

Iowa voters appear split on the 2020 Democratic presidential primary, according to a new poll that places four candidates within the margin of error for the top spot in the field. 

Former Vice President Joe Biden and Sen. Bernie Sanders (I-Vt.) are leading the primary field in the first-in-the country caucus state with 22 percent support each, according to a CBS News-YouGov poll released Sunday. 

South Bend, Ind., Mayor Pete Buttigieg closely trails at 21 percent, and Sen. Elizabeth Warren’s (D-Mass.) 18 percent also falls within the 4.1 percent margin of error, placing the four candidates in a statistical dead heat for the top spot in Iowa.

No other candidate registered double-digit support, with Sens. Kamala Harris (D-Calif.) and Amy Klobuchar (D-Minn.) tied in a distant fifth place with 5 percent each.  

Buttigieg has seen a 15-point uptick since a CBS-YouGov poll of Iowa voters in September that placed him at 6 percent support. 

Sanders’s support has increased 3 points since September, while Warren has seen a 10-point dip and Biden’s support has decreased 3 points in Iowa. 

Buttigieg saw a similar surge in a CNN poll released Saturday that placed him at him at 25 percent support, leading Sanders and Biden by 10 points and Warren by 9 points. 

The new CBS-YouGov poll surveyed 856 registered Democratic voters and was conducted between Nov. 6 and Nov. 13.