Sen. Bernie Sanders (I-VT) on Tuesday signed a pledge to run for president as a member of the Democrat Party.

Sen. Sanders has signed a loyalty pledge to the Democratic National Cmte., saying he is a member of the party and will run for president in 2020 only as a Democrat, his campaign and the DNC tell @NBCNews – @aseitzwald pic.twitter.com/RUv4Sp5nG0 — NBC Politics (@NBCPolitics) March 5, 2019

Sanders signed the “loyalty pledge” in response to the Democrat National Committee (DNC) passing a rule barring non-Democrats from seeking the party’s presidential nomination in 2020. Sanders ran for the White House in 2016 without declaring himself a Democrat, a move which irked party members across the country.

While the decision for Sanders to sign the pledge is sure to bring ease to Democrat officials, the move is not entirely surprising. Jeff Weaver, a senior campaign adviser to Sanders, told CNN that the presidential candidate intended to run as a Democrat in 2020 and had no issues putting it in writing.

Earlier this February, Sanders launched a second run for the White House, pledging to run a campaign focused on “transforming” the U.S. and “creating a government based on the principles of economic, social, racial and environmental justice.”

Following his announcement to seek the presidency, Sanders jumped six percentage points in a Morning Consult poll gauging support for 2020 Democrat presidential candidates. The polling company said his bounce in support was the “largest single-week shift for a candidate so far in Morning Consult’s tracking.”

Sanders, who now trails former Vice President Joe Biden in second place, increased from 21 percent of the possible primary vote share to 27 percent.