Merkel hit back at critics who said her above-the-fray campaign style bore part of the blame for the conservatives' losses in three regional elections held Sunday, which saw them likely to lose control of two states.
She said the races had no bearing on the September 27 poll, insisting that voters saw her conservatives and their favoured coalition partners, the pro-business Free Democrats, as best-placed to lead Germany out of a steep economic downturn.
"We all agree that in light of the crisis, the issues are economic growth and jobs," she told reporters after talks with leaders of her Christian Democrats (CDU) when asked about the internal criticism.
"It is clear that there is no reason to change anything at all about our strategy. We are absolutely on the right course."
Merkel's CDU enjoys a double-digit lead in the polls over the rival Social Democrats (SPD), junior partners in her unwieldy right-left grand coalition. Most pollsters say she is virtually assured of a second term. But her chances of ditching the SPD after the general election in favour of the Free Democrats appeared to narrow with Sunday's results.
Although the SPD failed to make major gains, a jubilant Foreign Minister Frank-Walter Steinmeier, Merkel's SPD challenger, saw her poor showing as a sign the centre-left still had a shot of snatching the chancellery from her.
"One thing is sure - this country does not want black-yellow," he said, referring to the party colours for the CDU and the Free Democrats.
The poll reversals so close to the election spooked many conservatives. Philipp Missfelder, a member of the CDU's board, urged Merkel to abandon her cool campaign style and show a bit more "passion."
"After an until-now sober and unpolitical election campaign, it is time for some more emotion," he said, adding his voice to a chorus of complaints.
Although the Free Democrats boosted their score in Sunday's polls, their general secretary Dirk Niebel also appeared nervous that the centre-right camp's strong lead would fizzle.
"If (Merkel's conservatives) don't start making clear what they would like to achieve then there is a great danger that they will blow it again because voters will think they want to continue with the grand coalition," he told public radio.
In the 2005 general election, the CDU squandered a sizeable lead to finish just ahead of the SPD, which forced it to form the current awkward right-left government. And in the previous election in 2002, the CDU unexpectedly lost outright to the SPD, allowing it to continue its coalition with the Greens.
Those defeats haunt the conservatives, making even Merkel's most ardent supporters skittish.
Political scientist Jürgen Falter of the University of Mainz in western Germany said the regional elections pointed to doubts about Merkel's preferred centre-right alliance.
"This option was always in danger and still is in danger," he told the daily Thüringer Allgemeine, predicting a close national race.
As pollsters expected, the CDU held on to power in the eastern state of Saxony but will need to link up with the Free Democrats to form a ruling majority.
And in what the mass-market daily Bild called a "debacle" for the CDU, it appeared to lose control of the legislatures of both neighbouring Thuringia and Saarland on the French border.
However, smaller parties profited from the conservatives' losses far more than the SPD, which posted slight gains in Thuringia and Saxony and a steep drop in support in Saarland.
But in Saarland at least, the SPD will likely be able to form a ruling coalition with the Greens and the socialist outfit The Left, a relatively new party made up of disaffected Social Democrats and former East German communists.