Washington (CNN) Democratic outside groups have largely sat on the sidelines when it came to attacking Republican incumbent Will Hurd in the Texas 23rd District. But no more.

The group "Women Vote!" has reported a half-a-million-dollar ad buy aimed at opposing Hurd, who is facing an increasingly competitive race with Democratic challenger Gina Ortiz Jones.

The $535,000 expenditure was part of trio of six-figure infusions made by the Democratic group over the last week, according to Federal Election Commission data. It also targeted Washington's 8th District and the Kansas 3rd.

The Texas race is Lean Republican in CNN's Key Race ratings , but the Washington and Kansas contests are both in the Toss Up column.

But the ad buy in Texas was by far the largest of the three, and shows the extent to which Democrats see the swing district as a pickup opportunity.

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