COLORADO SPRINGS (Colorado) • The Koch political network, which has steadfastly refused to engage in the 2016 presidential contest, plans to invoke Democrat presidential nominee Hillary Clinton in paid messages to voters as part of its campaigns backing Republican Senate candidates, top officials said.

"We are going to tie the Democrat candidates to Hillary Clinton and the failed policies that she supports, and highlight the differences with the Republican candidates that we favour and that we're supporting," said Mr Mark Holden, chairman of the board of Freedom Partners Chamber of Commerce, the network's funding arm.

But Mr Holden said last Saturday that the network has no plans to run an explicit campaign opposing Mrs Clinton's efforts to reach the White House, even after Republican presidential nominee Donald Trump's choice of Indiana governor Mike Pence, a Koch favourite, as his running mate: "We are going to differentiate on policies alone. It's not going to be anti-Hillary."

The plans come as the network is under pressure from some of its wealthy donors to get off the sidelines and use its national field infrastructure and paid advertising capacity to back Mr Trump. But Koch Industries chief executive Charles Koch has refused to budge, repeatedly expressing his dismay with Mr Trump's tone and policy positions.

Still, the invocation of Mrs Clinton in Koch-backed ads is another way that the operation could end up indirectly boosting Mr Trump.

Koch-backed groups have hundreds of staff in the field, gathering reams of data on voters in key battleground states that filter back to Republican candidates. The network's permanent ground force could also help propel Republicans to the polls in key states.

Moments before Mr Holden addressed reporters, Mr Trump tweeted that he had rejected a sit-down with the billionaire Koch brothers.

But Mr Holden said he was not aware of any discussions with Mr Trump's campaign about a possible meeting.

WASHINGTON POST