DUBLIN, Ohio (Reuters) - Becky von Zastrow often votes Republican in her affluent central Ohio suburb - but her dissatisfaction with U.S. President Donald Trump has convinced her to back the Democrat in a special-election test for both parties next month.

Her change of heart, reinforced by Trump’s handling of last week’s Helsinki summit with Russian President Vladimir Putin, could bode well for Democrat Danny O’Connor, a 31-year-old local officeholder running for an Ohio congressional seat Republicans have held since 1982.

In interviews with a dozen women, mostly Republicans, in the Midwestern state’s 12th Congressional District, several said they would buck their voting habits to support the Democratic candidate on Aug. 7, citing Trump as a major factor. Others said they disapproved of the president’s behavior but had yet to make up their minds about the congressional contest.

For von Zastrow and several other women in the Ohio district, Trump’s refusal at a July 16 news conference with Putin to criticize Russian interference in the 2016 U.S. presidential election affirmed their decisions.