"significant campaign" is correct and usable in written English.
You can use it to describe an influential or far-reaching promotional effort. For example, "Apple launched a significant campaign to promote their new iPhone model."
And you said you would lead the way for significant campaign finance reform.
The industry is a big employer in his state, not to mention a significant campaign contributor.
Many of these lawmakers, both Democrats and Republicans, have received significant campaign contributions from the industry.
For all that, the state spending limits are notoriously porous, with many significant campaign expenditures, like staff salaries, not counted against the cap.
With the assistance of Senator Jones, Mr. Obama helped deliver what is said to have been the first significant campaign finance reform law in Illinois in 25 years.
They attracted up to five thousand supporters — a thimbleful in a country of China's size, but a significant campaign in the context of a one-party state.
He has chosen able, articulate people to help him, and has raised significant campaign dollars from small as well as large donors.
Republican opponents and the financial industry, which provided significant campaign backing for Mr. Obama, say his proposal and his rhetoric go too far.
But even as he extols the old Harlem, he is generating significant campaign contributions from those at the forefront of the new.
While the Manhattan-based agencies were not significant campaign donors to Mr. Schumer or the Senate campaign committee, their lobbyists and many of their clients were.
All four lawmakers made their inquiries about Menaflex after receiving significant campaign contributions from ReGen, which is based in Hackensack, N.J.
