Ms Davidson also warned that senior Nationalist MPs like Westminster leader Angus Robertson in Moray and Pete Wishart in Perth and North Perthshire could be vulnerable to the Tories after they overtook Labour to become the second party in Scotland at last year's Holyrood election.
Ms Davidson today ruled out standing in the forthcoming election as an MP, but said "three or four" of her MSP colleagues could run for Westminster.
And the Edinburgh Central MSP insisted that the Tories will win more than the one seat they secured in the 2015 general election, while the SNP will fall short of the 56 seats they won two years ago.
"We're the strongest party to take on the SNP," Ms Davidson said today.
"I know there was talk at the general election a couple of years ago about tactical voting and I've not been a particular proponent of it, but I think if you do believe in tactical voting and if you have a principled belief in keeping the United Kingdom together and respecting the decision that we made in 2014, then actually your vote is for the Scottish Conservatives.
"You've got a Labour leader in Jeremy Corbyn who said he'd be quite happy to let another referendum happen, the Lib Dems just aren't strong enough and that's not indication of how hard they work, but you see the kind of percentages they get across the country, the fact they've fallen to the fifth party in the Scottish Parliament.
"It is very much a case, if you're not supporting the SNP and you want somebody to stop their drive t break up Scotland then the Scottish Conservatives are you best bet."
Ms Davidson pointed to last year's Holyrood election when the Tories won a number of constituency seats in the South of Scotland, Ayrshire, the Borders and West of Scotland, while the party also doubled it's vote share in many northern areas where it finished second to the SNP.
"If you're talking about Angus Robertson (Moray), if the line from the SNP in this general election is going to be talking about Brexit as much as they can, well 49.6% of his seat voted to leave, so you know, my strong prediction is there's no way the SNP is getting 56 this time."
She also indicated that party will have a "right good go" at securing the Perthshire seat held by Mr Wishart.