In a new Reuters poll, more people said they would vote for a Republican candidate over a Democrat in the upcoming midterm election, a reversal of previous trends.

Of the 1,139 people surveyed earlier this month, 40.4 percent said they would vote for a Republican in their district in November, up from 32.4 percent of those who were surveyed in December 2017. Only 34.5 percent of respondents said they planned to vote for a Democrat in their district in the upcoming election, down from 45.5 percent in December.

The Real Clear Politics poll average, which has not yet incorporated the latest data from this weekly Reuters poll, shows that Democrats have a four-point lead over Republicans. This lead is a significant drop from the 12.9 lead Democrats held at the beginning of January.

Dwindling Democratic support comes amid widespread talk of a “Blue Wave,” the expectation that Democrats will win back the House of Representatives and possibly the Senate in November. You can track the swelling Republican support and dwindling Democratic support as tracked by Reuters, here.