By Jason Lange and Jarrett Renshaw WASHINGTON (Reuters) -Fundraising groups tied to Republican Party leaders are sharply increasing spending on campaign ads to help the party win control of Congress in the Nov. 8 general elections. But not Donald Trump’s Save America, a PAC fundraising group that under U.S. election law can fund the Republican former president’s political allies and his frequent rallies but not any election campaign of his own. Despite amassing more than $90 million in the PAC – an unprecedented sum for a former leader – Trump’s group has yet to report any ad spending to suppo…